Method of cleaning steel and imparting rust-inhibitive properties thereto and solution therefor



-' v Patented July 1 1,',1'925.

solution containing a'small percentage of a rust-attacking and removingacid, such as UNIT-ED STA;

" JAMES n; KLINGERND cLETE L. BClYLE, 0E n'ETno IT, MICHIGAN, AssIGNoEsTo GHEMICAIL PRODUCTS CORPORATION," OF DETROIT, MICHIGAN.

METHOD or CLEANIN sTEEE AND mmmm nosT-mmrTrvE ritorEaTrEs- THERETO ANDSOLUTION THEnEEoE. v

No Drawing.

To all it may concern:

1 Be it known that we,

States, residing at Detroit, county of certain new and usefulImprovement in Methods of Cleaning Steel and Imparting RustlnhibitiveProperties Thereto and Solution Therefor, and declare the following tobe a full clear, and exact description of the same, such as'will enableothers skilled in the art to which it pertains to make and use the same.

This invention relates to an improved inhibitive properties, thereto,and the objectof our invention is to provide an improved method andagent-by means of which steel may be cleanedand rust inhibitiveproperties may be imparted to the metal.

More specifically, an object is to provide a cheap, inexpensive, rapidprocess for removing oil, grease, dirt, rust, etc., from the surface ofsteel, such as for example, the sheet steel generally employed in themanufacture of automobile bodiesyand at the same time imparting to thesurface of the steel rust inhibitive properties which will revent thesteel from subsequently corroding and rusting.

"Our improved method for treating steel and solution employed thereinis' particularly useful in preparing the metal for painting. Byfollowing this process the steel is thoroughly cleaned so as to receive[and retain 'a-priming coat of paint and the surface of .the metal isrendered substantially immune to the-action of rust either before orfollowing the painting. We: have. found that by using a soluble salt ofchromic acid, such'as otassium chro- 1 mate or sodium. chromate, in ourcleaning solation thatsthe rust inhibitive properties of the chnomatepreventthe-steel from subsequent rusting. W'e provide a cleaningrem'ovaloidirt is-employed. In this case we use an alcoholor acetone. Ithas been found that denaturedalcohol containing a s ell JAMES D.KLINGER. and CLETE L. BOYLE, citizens of the United I lVayne, State ofMichigan, have invented amethod of cleaning steel and imparting rust".body construction:

Application filed Hay, 1924. Serial No. 713,778.

amount ofacetone performs very satisfactow.

e have found that an admixture of chromic acid or any soluble saltthereof or any soluble compound containing chromium with sulphuric acid,hydrochloric acid,'nitric acid, or such other acid as possesses theproperty of attacking and removing rust from metal will serve to impartto the surface of 'the metal when cleaned by the rust-removacid,rust-resisting qualities, and that this process is particularly valuableas a treatment for metal preparatory to paintingghe metal. I r

' e prefer to employ a' fluid-mixture of potassium or sodium chromate,sulphuric acid, denaturedalcohohand acetone. This solution when appliedto the metal will remove all oil, dirt, grease, rust, etc., and give thesurface of the metal a bright, clean finish and impart thereto rustresisting properties. This solution may be applied to the metal with abrush, sponge, spray, or in any other suitable 'manner. It may beapplied either hot or cold. It has been found that if the rust isdeep-seated ahot solution will act more quickly than a cold solution; Asa further aid in removing deep-seated rust after the solution'has beenapplied to the metal the badly rusted spots may similar abrasive.

The following method has been found suitable for use in connection withpre aring the sheet steel employed in automo ile The metalis painted or'spra deep-seated action is accelerated by rubbing the rusty.

spots with emery cloth or a'suitable abrasiye',

being taken to keep the spot wetwith' the cleaning solution; A period oftwo to care be rubbed with emery cloth or other ed with the cleaningsolution. In cases w ere there is rust on the steel the cleaning threeminutes is allowed for the solution to act. The cleaning solutioniandthe resultant products of the cleaning action are then washed from thesteel by. or cold water. If cold water is used it should be flowed "onfreely and the water remaining on the surface blown off with air." Ifhot water is used any water'that has not evaporated should be-blown offwith air. The method for proceeding from this rinsing with hot point isto torch oif'ai'ound moulding Qt pockets with a gas'flame, when cleaningall} tomobile bodies, to drive out water. The steel should then be wipedwith a cloth saturated with turpentine or alcohol and placed in apre-heat oven to dry. The steel "is then ready for the priming coat ofpaint.

The strength of the solution may be Varied depending" upon the Work tobe accomplished. A solution of the following ingredients in theproportions setvforth' has been found very satisfactory: four parts ofan aqueous solution of potassium or sodium chromate (strength ofsolution 5%), onehalf of one part of concentrated sulphuric acid, fourand one-half parts of denatured alcohol, and one part of acetone.

What we claim is:

1. The method of cleaning steel and imparting thereto rust inhibitiveproperties consisting in treating the metal with a solution containing asoluble salt of chromic acid, sulphuric acid, and an alcohol.

2. The method of cleaning steel and iniparting rust inhibitiveproperties thereto which consists in treating the metal with a solutioncontaining sulphuric acid, -a'

soluble chromate, an alcohol, and acetone.

3. The method of cleaning steel and imparting thereto rust inhibitiveproperties which consists'intreating the metal Wibh a solutioncontaining sulphuric v acid, a soluble chromate, apd acetone.

4. The method .ofcleanihg steel and imparting thereto rust inhibitiveproperties.

which consists in treating the metal with a solution containingpotassium' chromate,

sulphuric acid,'and an alcol kol...

5. The method of cleaning steel and imparting thereto rust inhibitiveproperties which consists in treating the metal with which consists intreating the metal with a solution composed of denatured alcohol, an

aqueous solution of a soluble chromate, and

a relatively small percentage of sulphuric acid.

7. A solution to. be used in the cleaning,

of steel and the impartingof rust inhibitive properties to the surfacethereof containingthe followin ingredients in the approximate volume offour parts of an aqueous solution of asolulole chromate, four and a halfparts of an alcohol, one part of" acetone, and one ha-lf of one partsulphuric acid.

8. A solution to be used for cleaning steel and imparting rustinhibitive properties thereto containing an alcohol, a rust-removingacid, and a solution of a soluble salt of chromic acid.

'9. A solution to be used in the cleaning of steel and the imparting ofrust inhibitive properties thereto comprising denatured alcohol,acetone,- sulphuric acid, and an aqueous-solution of a salt ofchromicacid.

10. A solutionto be used in the cleaning of steel and the imparting ofrust inhibitive properties thereto containing an alcohol, sulphuricacid, and potassium chromate.

11. A solution t'o-be, used in the cleaning of steel and the impartingof rust inhibitive properties thereto containing an alcohol, sulphuricacid, and sodium chromate.

In testimony whereof, we sign this specification.

' JAMES D. KLINGER. CLETE L. BOYLE.

